Excavator shield and side cutter



j. C. FRENCH,

EXCAVATOR SHEELD AND SIDE CUTTER.

APPLiCATiON HLED FEB. 25, i918.

Patented Oct. 7,1919.

3 SHEETS-SHEET I.

mmsem J. C.-FRENCH.

EXCAVATOR SHIELD AND SIDE cunen.

APPLICATION .FILED FEB. 25.1913.

Patented Oct. 7, 1919.

3 SHEETS-SHEET 2.

Lmmwq J.'C. FRENCH.

EXCAVATOR SHIELD AND sens CUTTER.

APPLlCATlON FILE!) PEB 25,1918.

Patented Oct. 7, 1919.

3 SHEETS- SHEET 3.

JAMES c. FRENCH, or CHICAGO, ILLINOIS, ASSIGNOR 'I'O FREDERICK c. AUSTIN, or

CHICAGO, ILLINOIS.

EXGAVATOR SHIELD AND SIDE CUTTER.

Specification of Letters Patent.

Patented Oct. 7, 191a.

Application filed February 25, 1918. Serial No. 218.938.

The invention relates to excavators of that kind in which a tilting digging beam is arranged at the rear end of the machine and provided with an endless series of buckets by which the trench is out while the machine is slowly traveling forward.

Generally stated, the objectof the invention is to provide'a novel and improved trenching machine of the foregoing general character.

A special object is to provide an improved construction and arrangement whereby a shield construction is employed to facilitate the work in the ditch, such as the laying of tile behind the trenching machine, and whereby sufficient clearance is produced at each side of the trench for the sides of the shield construction. so that the entire structure will slide forward behind the excavating buckets. 7

It is also an object to provide certain details nd features of construct-ion and combinations tending to increase the general efficiency and desirability of a trenching machine of this particular character.

To the foregoing and other useful ends, the invention consists in matters hereinafter set forth and claimed. and illustrated in the accompanying drawings, in which Figure 1 is a side elevation of a trenching machine embodying the Principles-of the invention, showing the front end thereof broken away for convenience of illustration.

Fig. 2 is a plan of the structure shown in Fig. 1.

Fig. 3 is an enlarged vertical section on line 3-3 in Fig. 1.

Fig. 4 is a vertical section on line 4-4 in Fig. 1.

As thus illustrated, the invention comprises a body frame 1 mounted on traction devices 2, of any suitable character, and op eratcd by an engine or motor. (not shown) usually located near the front end of said body frame. The tilting digging beamSis mounted on the transversely arranged shaft 4, suitably supported at the rear end of the body frame, so that said digging beam is adapted to tilt up and down about a transverse axis. Sprocket chains 5 are carried on said digging beam, being mounted on sprockets arranged at the upper and lower ends of said digging beam, in the usual manner, so that the digging'buckets 6, of any suitable character, mounted on said sprocket chains, will cut the trench and become loaded with loose dirt as they travel upward against the inclined breast 7 of the trench, and will discharge their loads at the upper end of the beam, as they pass over the upper sprocket wheels, in the usual and well known manner. Any suitable arrangement can be employed for raising and lowering the digging apparatus thus arrangedto trail behind the machine to cut the-trench.

To facilitate the work of .laying tile, or I to prevent caving in of the banks of the trench, while working in soft ground, im-

mediately behind the digging apparatus, a

pair of side shields 8 is provided and suitably supported on the digging beam. The sprocket chains 5 and the buckets 6 travel between these two shields which travel forward with the machin close to or against the sides of the trench. A ditch shield travels immediately behind the lower end of the digging apparatus, this ditch shield comprising side walls9 suitably connected together and provided at their lower ends with a shoe 10 which slides along on the bottom of the trench. The walls 9 telescope within the side shields 8, and are equipped with a curved bucket shield 11 which curves downwardly and then forwardly behind the buckets, in front of the shoe 10, so that all the loose dirt is forced ahead of the ditch shield and into position to be takenup by the buckets as they travel downward and around the lower sprockets and then start upward at the bottom of the trench. The ditch shield is also provided with a rigid upright frame 12, of any suitable shape, having its upper end pivoted at 13 to the rear end of the brace 14, which latter has its front end pivoted at 15 upon the upper structure 16 of the digging beam. Draft chains or other connections '17 connect the side strips 18 of the ditch shield with the brackets 19 on the rear end of the body frame, and in this way the ditch shield is pulled forward behind the digging apparatus when the traction devices 2 are operated to propel the machine forward. The ditch shield comprising the two side walls 9 is open at its rear end, so that workmen may stand within the shield while the excavating operation is in progress, thereby to facilitate the laying of the tile immediately behind the ditch shield. Also, the bottom of the ditch shield can be open, more or less, so that in very's'oft ground the tile can be laid immediately behind the lower end of the digging apparatus, and between the banks or sides of the trench which are being held up or revented by the walls 9 from caving in wliile the work is in progress. v

The side shields 8 require clearance at the sides of the trench, as they are farther apart than the width of the buckets 6, and to produce this clearance side-cutters 20 are provided on the auxiliary chains 21 which are carried by sprockets 22 disposed at suitable points on the sides of the digging beam. .hese auxiliary side chains 21 are driven by a sprocket connection 23 which extends to the shaft 4 previously described, whereby the rotation of this shaft to operate the bucket 6 will also 0 erate the side-cutters 20, these cutters trave ing upward against the sloping breast of the trench, but not cutting quite as deeply as do the buckets, whereby the breast of the trench will have a shoulder 24 at each side thereof. The side-cutters 20, however, operate immediately in advance of the side shields 8, so that. the latter move forward in the space or clearance produced by these cutters. I v

In this way, the side shields, and the ditch shield in rear thereof, are enabled to move forward without binding against the sides of the trench, in order to hold u the banks and prevent them from caving in while the machine is working in'soft ground. When the digging apparatus is raised or swung upward, the bucket shield 11 will rest against the buckets 6, at the lower end of' the digging apparatus, and the digging beam will thus carry the ditch shield upward, the chain 17 being suitably manipulated to accomplish this purpose. A derrickarm 25 can 'be mounted on the frame 12 to facilitate the lowering of the tile or other materials into the ditch shield, or into the trench behind the trench shield, as will be readily understood. A pull exerted on the chain 17 by the forward movement of the machine would tip the ditch shield over were it not for the brace 14 previously described. This brace, of course, keeps the frame 12 upright so that the pull on the chain 17 slides the lower end of the ditch shield forward behind the digging apparatus.

The auxiliary side cutters 20, it will be seen, operate in the vertical planes of the two side walls 8, and these vertical planes are spaced a distance from the sides of the from caving in while the machine is working in soft ground. Also, the buckets 6 and the cutters 20 travel upwardly in the same 1nclined plane while cutting forward into the ground to form the trench.

What I claim as my invention is:

1. In a trenching machine, the combination of a body adapted to travel forward on the ground, a digging apparatus thereon in position to cut a trench behind said body, side shields for said digging apparatus spaced apart a distance greater than the width of the trench, and devices for cutting into the ground ahead of said shields to widen the trench and provide clearance at the sides thereof for said shields.

2. A structure as specified in claim 1, said link-belts in line with said shields.

4. A structure as specified in claim 1, said apparatus comprising a swinging digging beam, and said shields being disposed at .opposite sides of the plane of said beam and in the planes of said devices.

5. A structure as specified in claim 1, in combination-with a hollow structure adapted to rest on the bottom of the trench immediately behind said apparatus to cooperate with said shields to prevent the sides of the trench from falling inward, and means to connect said hollow structure with said traveling body.

6. A structure as specified in claim 1, and a hollow body adapted to rest on the bottom of the trench immediately behind said apparatus, the front portion of said hollow structure extending between said shields, an upright member for said hollow structure, a brace to connect the upper end of said member with the trenching machine, and a draft connection between the top of said structure and the rear end of said traveling body.

7. In a trenching machine, the combination of a body adapted to travel forward on the ground, a digging apparatus thereon in position to cut a trench behind said body, side shields for said digging apparatus, and devices for cutting into the ground ahead of said shields to provide clearance therefor at the sides of the trench, said apparatus comprising a swinging digging beam, and said shields being mounted on said beam.

8. In a trenching machine, the combination of a body adapted to travel forward on the ground, a digging apparatus thereon in position to cut a trench behind said body, side shields for said digging apparatus, and devices for cutting into the ground ahead of said shields to provide clearance therefor at the sides of the trench, in combination with a hollow structure adapted to rest on the bottom of the trench immediately behind said apparatus to cooperate with said shields to prevent the sides of the trench from falling inward, and means to connect said hollow structure with said traveling body.

9. In a trenching machine, the combination of a body adapted to travel forward on the ground, a digging apparatus thereon in position to cut a trench behind said body, side shields for said digging apparatus, and devices for cutting into the ground ahead of said shields to provide clearance therefor at the sides of the trench, and a hollow body adapted to rest on the bottom of the trench immediately behind said apparatus, the front portion of said hollow structure extending between said shields, an upright member for said hollow structure, a brace to connect the upper end of'said member with the trench machine, and a draft connection between the top of said structure and the rear end of said traveling body.

10. In an excavator, the combination of an endless series of buckets for cutting a trench, a sprocket chain at each side of said series of buckets, cutting means on said sprocket chains to widen the trench cut by the buckets, said sprocket chains being disposed in parallel vertical planes which are spaced a distance from the sides of said series of buckets, side shields disposed in said planes behind the sprocket chains, and a support for said buckets and sprocket chains.

11. In a structure as specified in claim 10, said cutting means and said buckets be-' ing disposed in the same transverse inclined plane of movement while traveling upwardly to cut the trench.

12. A structure as specified in claim 10,

said shields being adapted tobear against the sides of the trench and being also disposed in the vertical planes of said cutting 7 means, and said buckets traveling downwardly upside down between said planes.

13. In an excavator, the combination of a swinging trench cutter which is movable up and down about a transverse axis, a hollow body having walls to bear against the sides of the trench behind the trench cutter, adapted to slide on the bottom of the trench, a draft connection extending from the upper portion of the hollow body to the excavator, a post extending upwardly from said body, a pivoted brace extending rearwardly from the excavator to the upper portion of said post, said hollow body hava trench cutter, a hollow body having side walls to bear against the sides of the trench in rear of said trench cutter, the said body.

being wider than the trench made by said trench cutter, and auxiliary cutters for widening the trench in advance of said body, said trench cutter operating between the two side walls.

16. A structure as specified in claim 10, said buckets beingv disposed between the two side walls while traveling downwardly in the trench.

Signed by me at .Chicago, Cook county, Illinois, this twelfth day of February, 1918.

JAMES C. FRENCH. 

